Treatment of textile materials



2,731,368 TREATIVIENT F TEXTILE MATERIALS No Drawing. Application February 20, 1952, Serial No. 272,686

1 Claim. (Cl. 117-4394 This invention relates to the treatment of textile ma terials and relates more particularly to the treatmentof textile materials having a basis of cellulose acetate or other organic derivative of cellulose.

An important object of this inventionis to impart an improved resistance to creasing to textile materials having a basis of cellulose acetate or other organic derivative of cellulose; T

A further object of this invention is to incorporate onto textile materials having a basis of cellulose acetate or other organic derivative of cellulose a small proportion of an elastomer whereby the resistance to creasing of said textile materials is greatly improved.

Other objects of this invention will be apparent from the following detailed description and claim.

It has long been known that-an improvedresistance to creasing may be imparted to textile materials, such as fab- States Patent 0 rics and the like, having a basis of cellulose, such as cotton, regenerated cellulose and the like, by incorporating into said textile materials certain synthetic resins of the urea-formaldehyde and melamine-formaldehyde class. The synethic resins are applied to the cellulose textile materials in a partially polymerized state, or components capable of forming said resins are applied to the cellulose textile materials, following which the materials are heated or otherwise treated to elfect or complete the polymerization of the resins. The resins enter into the filaments and fibers themselves and change the physical characteristics thereof. Attempts to apply these and similar treatments to textile materials having a basis of cellulose acetate or other organic derivative of cellulose have, however, failed to improve the resistance to creasing of said textile materials and have, in some cases, actually rendered the said textile materials more liable to creasing. As a result, there has been little or no commercial use of anti-crease treatments on textile materials having a basis of cellulose acetate or other organic derivative of cellulose.

According to the present invention, it is possible to improve the resistance to creasing of textile materials having a basis of cellulose acetate or other organic derivative of cellulose by incorporating onto said textile materials a relatively small amount of an elastomer. Cellulose ace tate textile materials, for example, treated in this manner not only display an improved resistance to creasing, but also have a firmer hand and a fuller body than the untreated textile materials without any tendency toward stiffness.

Elastomeric materials that are suitable for use in accordance with the present invention include, for example, polyvinyl butyral, vinyl chloride-vinylidenechloride co polymers and butadiene-styrene copolymers (Buna S). The elastomers may be applied to the textile materials from solution in organic solvents which will not dissolve the cellulose acetate or other organic derivative of cellulose. However, they are preferably applied to the textile materials from an aqueous dispersion or latex containing, if desired, a suitable dispersing agent. The elastomers of this invention are applied to the textile materials in their 2,731,368 Patented Jan. 17, 1956 fully polymerized state and require no further polymerization. This represents an important saving over the use of partially polymerized resins or the components of resins used-in treating cellulose textile materials both in eliminating the polymerization step and in avoiding possible damage to the textile materials as the result of the conditions necessary to efiect the polymerization. The elastomers may be employed per se or they may be mixed with a plasticizer to impart a greater flexibility thereto. There may also be added to the elastomer, dyes, pigments, ultra-violet light absorbents, fire-retardants and other effect materials. The elastomers referred to above are characterized by having a high elongation when subjected to stress and a high recovery following removal of said stress.

In applying the elastomer to the textile materials, use may be made of conventional textile apparatus adapted for this purpose. For example, the textile materials may be passed through a latex of the elastomer and then between a pair of nip rolls to express from the textile materials the excess of latex adhering thereto above a predetermined amount. The textile materials may then be dried in a tenter or the like, following whichthey may be subjected to conventional treatments such as calendering, decatizing, button breaking'and the like depending on the finish desired on the said textile materials.

The quantity of elastomer applied to the textile materials is critical and should not exceed about 2.0% by weight or preferably about 0.625%. by weight and should range from about 0.1 to 2.0% by weight based on the weight of the textile materials. When the larger quantities of elastomer than those specified are applied, the textile materials actually exhibit a greater tendency to crease than untreated textile materials. This is surprising' because in the treatment of cellulose textile materials with resins to improve the crease resistance thereof, it is common to employ at least 5% by weight of the treating agent and to go up to as high as 30% by weight of the treating agent with an improved resistance to creasing as the quantity of the treating agent is increased.

It is believed that the elastomer improves the resistance to creasing of the treated textile materials by forming elasticweld bonds between adjacent filaments and filament bundles without actually entering into or changing the physical properties of the filaments themselves. When the textile materials are creased, these weld bonds tend to prevent shifting of the filaments and filament bundles relative to one another and also provide an elastic restoring force once the crease producing force is removed. That this mechanism is probably correct is evidenced by the fact that the elastomer containing textile materials show an improved resistance to creasing not only on a short term basis, but also on a long term basis. Thus, if an elastomer treated textile material is creased by folding the same and applying a definite weight thereto for a given period of time, the recovery angle of the textile material will be greater than that of an untreated textile material both 5 minutes after the weight is removed and 24 hours after the weight is removed. When a higher proportion of elastomer than that specified above is employed, it seems to fill the spaces between the filaments and filament bundles and, depending upon the precise amount of elastomer employed, approaches more or less closely to the state of a film so that the elastic weld bonds are incapable of functioning in the foregoing manner.

This invention will now be described specifically in connection with the treatment of cellulose acetate textile materials since cellulose acetate is the most important organic derivative of cellulose at the present time. It may also be applied to the treatment of textile materials having a basis of other organic derivatives of cellulose textile .materials such as for texample -other lower ali- :bc' formed of-ac'on'tinuou's filamentsor staple fibers ofan organiederivativvof cellulose or- 'of a niiiiture of orgariic derivatives 1 of cellulose filamentary materials with" other natural orsynthetic fibers or filam'erits;

The following examples are given 'to illustrate ithis' i'rb ventionfur'ther.

Example I .Atfabric twoventinfazplain weave-from cellulose a'cetate yarns isaimrnersedior 3.0 secondsin'to a=latex of 'a'polyvinyl zbutyral plasticized -with '80% 'by weightof 'but'y'l i icinoleate, based on theweight of-the polyvinyl o'utyral, and maintained at. '50 1C. The 'fabr'ic is then passed between nip rolls adjusted to give a wet pick up of thela'tex inathe amount of 50% following' which the rabrieis dried at 70 C. and allight steam pressing. I'hedri'ed fabric :contains ;625 by weight of the plastieized=polyvinyl butyrzil. A sample dfithe fabric ?is conditioned-for 12 hours 'at124 C.tand 65% relativehumiditygfoldedtantl plaeediior 5 minnteslunder ia 1.000 gram -Weight. ifift'cr removal of :the :weight, i the 'treated 'fzibricxeiihibits a recowery .134 degrees after 5 minutesand :154 degrees after 24 :hours. An untreated sample of the same fabri'c', When erease'd in the same manner,:e)ihibits arecover-y of only 98 degrees after 5 minutes and only l 4'2'degrees after 24 hours. An euntre'ated :sample 0f the same fabric when wetted and dried before creasing-exhibits axre'covcry of onlyr92 dcgreesiafter S-rninutes and ll4 degrees'after 24 hours.

Example 11 Example 111 The fabric described in Example I is immersed for 30 :seconds into a latex of polyvinyl :butyral plasticized with 40% by weight ofbutylricinoleate-and maintained at 50 *C. Thefabrieismeateddn 'themannerset'forth Example IV The fabric described :in *Example 'I is immersed I for seconds 'into a Slater'of -a"Biina"S 'butadiene styrene copolymer maintained at 50"" C; The fabric 'is treated in the manner "set forthini'Example /I :and, after drying contains 0.625% by we'ight'of the copolymer. Upon creasing in the manner ..setforth =in Example I, the treated fabric exhibits a recovery of""1"44 degrees after 5 minutes and 165 degrees after 24 hours. When the weight of the copolymer applied to the fabric is increased to 1.25%, the angle of recovery tir'q s' slightly although .it' is still markedly better i'than o'f"'the"untreated ffabric.

'It"'is"'to be" understoodthat Ithe f foregoing detailed description is given merely'by'way of illustration and that many vatiationsmay betniaiie Therein without dep arting Ha'ving"describe'ti'our"invention, what we desire to secure by Letters Patentis:

Procesf'for iimprovirigthe resistance to creasingof a textile'm'aterial containing'c'ellulos'e acetate yarn, which comprises immersing the said fabric "for 30' seconds into a latex "of 'a fully polymerized" bntadiene-styrene copolymer maintained at 5.0 C "and dryingtthe so treated .tex tile materialft'he pr'oportionldf the copolymer'retained on said textile material"being".0i6'25%' "by weight, based on the weight 'of'the textilemate'rial.

References Cited in the"file"df this patent UNITED STATES PATENTS GreatBritain -5-. of .1940 

